net: dsa: sja1105: Implement state machine for TAS with PTP clock source

Tested using the following bash script and the tc from iproute2-next:

	#!/bin/bash

	set -e -u -o pipefail

	NSEC_PER_SEC="1000000000"

	gatemask() {
		local tc_list="$1"
		local mask=0

		for tc in ${tc_list}; do
			mask=$((${mask} | (1 << ${tc})))
		done

		printf "%02x" ${mask}
	}

	if ! systemctl is-active --quiet ptp4l; then
		echo "Please start the ptp4l service"
		exit
	fi

	now=$(phc_ctl /dev/ptp1 get | gawk '/clock time is/ { print $5; }')
	# Phase-align the base time to the start of the next second.
	sec=$(echo "${now}" | gawk -F. '{ print $1; }')
	base_time="$(((${sec} + 1) * ${NSEC_PER_SEC}))"

	tc qdisc add dev swp5 parent root handle 100 taprio \
		num_tc 8 \
		map 0 1 2 3 5 6 7 \
		queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \
		base-time ${base_time} \
		sched-entry S $(gatemask 7) 100000 \
		sched-entry S $(gatemask "0 1 2 3 4 5 6") 400000 \
		clockid CLOCK_TAI flags 2

The "state machine" is a workqueue invoked after each manipulation
command on the PTP clock (reset, adjust time, set time, adjust
frequency) which checks over the state of the time-aware scheduler.
So it is not monitored periodically, only in reaction to a PTP command
typically triggered from a userspace daemon (linuxptp). Otherwise there
is no reason for things to go wrong.

Now that the timecounter/cyclecounter has been replaced with hardware
operations on the PTP clock, the TAS Kconfig now depends upon PTP and
the standalone clocksource operating mode has been removed.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/net/dsa/sja1105/sja1105_ptp.h b/drivers/net/dsa/sja1105/sja1105_ptp.h
index 83d9d4ae6d3a..470f44b76318 100644
--- a/drivers/net/dsa/sja1105/sja1105_ptp.h
+++ b/drivers/net/dsa/sja1105/sja1105_ptp.h
@@ -22,6 +22,8 @@ static inline s64 sja1105_ticks_to_ns(s64 ticks)
 }
 
 struct sja1105_ptp_cmd {
+	u64 ptpstrtsch;		/* start schedule */
+	u64 ptpstopsch;		/* stop schedule */
 	u64 resptp;		/* reset */
 	u64 corrclk4ts;		/* use the corrected clock for timestamps */
 	u64 ptpclkadd;		/* enum sja1105_ptp_clk_mode */
@@ -69,6 +71,9 @@ int __sja1105_ptp_settime(struct dsa_switch *ds, u64 ns,
 
 int __sja1105_ptp_adjtime(struct dsa_switch *ds, s64 delta);
 
+int sja1105_ptp_commit(struct dsa_switch *ds, struct sja1105_ptp_cmd *cmd,
+		       sja1105_spi_rw_mode_t rw);
+
 #else
 
 struct sja1105_ptp_cmd;
@@ -110,6 +115,13 @@ static inline int __sja1105_ptp_adjtime(struct dsa_switch *ds, s64 delta)
 	return 0;
 }
 
+static inline int sja1105_ptp_commit(struct dsa_switch *ds,
+				     struct sja1105_ptp_cmd *cmd,
+				     sja1105_spi_rw_mode_t rw)
+{
+	return 0;
+}
+
 #define sja1105et_ptp_cmd_packing NULL
 
 #define sja1105pqrs_ptp_cmd_packing NULL